• Title/Summary/Keyword: height information

Search Result 2,070, Processing Time 0.027 seconds

Accuracy Analysis of DEMs Generated from High Resolution Optical and SAR Images (고해상도 광학영상과 SAR영상으로부터 생성된 수치표고모델의 정확도 분석)

  • Kim, Chung;Lee, Dong-Cheon;Yom, Jae-Hong;Lee, Young-Wook
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2004.04a
    • /
    • pp.337-343
    • /
    • 2004
  • Spatial information could be obtained from spaceborne high resolution optical and synthetic aperture radar(SAR) images. However, some satellite images do not provide physical sensor information instead, rational polynomial coefficients(RPC) are available. The objectives of this study are: (1) 3-dimensional ground coordinates were computed by applying rational function model(RFM) with the RPC for the stereo pair of Ikonos images and their accuracy was evaluated. (2) Interferometric SAR(InSAR) was applied to JERS-1 images to generate DEM and its accuracy was analysis. (3) Quality of the DEM generated automatically also analyzed for different types of terrain in the study site. The overall accuracy was evaluated by comparing with GPS surveying data. The height offset in the RPC was corrected by estimating bias. In consequence, the accuracy was improved. Accuracy of the DEMs generated from InSAR with different selection of GCP was analyzed. In case of the Ikonos images, the results show that the overall RMSE was 0.23327", 0.l1625" and 13.70m in latitude, longitude and height, respectively. The height accuracy was improved after correcting the height offset in the RPC. i.e., RMSE of the height was 1.02m. As for the SAR image, RMSE of the height was 10.50m with optimal selection of GCP. For the different terrain types, the RMSE of the height for urban, forest and flat area was 23.65m, 8.54m, 0.99m, respectively for Ikonos image while the corresponding RMSE was 13.82m, 18.34m, 10.88m, respectively lot SAR image.

  • PDF

Estimation of the Potato Growth Information Using Multi-Spectral Image Sensor (멀티 스펙트럴 이미지 센서를 이용한 감자의 생육정보 예측)

  • Kang, Tae-Hwann;Noguchi, Noboru
    • Journal of Biosystems Engineering
    • /
    • v.36 no.3
    • /
    • pp.180-186
    • /
    • 2011
  • The objective of this research was to establish the estimation method of growth information on potato using Multi-Spectral Image Sensor (MSIS) and Global Positioning System (GPS). And growth estimation map for determining a prescription map over the entire field was generated. To determine the growth model, 10 ground-truth points of areas of $4m^2$ each were selected and investigated. The growth information included stem number, crop height and SPAD value. In addition, images information involving the ground-truth points were also taken by an unmanned helicopter, and reflectance value of Green, Red, and NIR bands were calculated with image processing. Then, growth status of potato was modeled by multi-regression analysis using these reflectance value of Green, Red, and NIR. As a result, potato growth information could be detected by analyzing Green, Red, and NIR images. Stem number, crop height and SPAD value could be estimated with $R^2$ values of 0.600, 0.657 and 0.747 respectively. The generated GIS map would describe variability of the potato growth in a whole field.

Efficient Simplification of a Height Map (지형 데이터의 효율적 단순화)

  • Park, Sang-Chul;Kim, Jung-Hoon;Chung, Yong-Ho
    • Korean Journal of Computational Design and Engineering
    • /
    • v.17 no.2
    • /
    • pp.132-139
    • /
    • 2012
  • Presented in the paper is a procedure to extract simplified triangular mesh from a height map (terrain data). The proposed algorithm works directly on a height map that extracts a simplified triangular mesh. For the simplification, the paper employs an iterative method of edge contractions. To determine an edge to be contracted, the contraction cost of an edge is evaluated through the QEM method. Normally, an edge contraction will remove two triangles sharing the edge. Although the edge contraction can be implemented easily on a triangular mesh, it is not viable to implement the operation on a height map due to the irregular topology. To handle the irregular topology during the simplification procedure, a new algorithm is introduced.

Varietal Classification on the Basis of Cluster Analysis in Burley Tobacco of N. tabacum L. (Cluster분석에 의한 버어리종 담배품종의 분류)

  • Ann, Dai-Jin;Kim, Yoon-Dong
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.5 no.2
    • /
    • pp.25-32
    • /
    • 1983
  • To obtain basic information on the breeding of burley tobacco, classification of 41 varieties was carried out by using the cluster analysis of correlation coefficients and taxonomic distance based on twenty-one agromonic characters. Eight characters, such as days to flowering, length of flower axis, internode length, leaf length, yield, leaf angle to stem, vein angle to midrib and plant height, were useful in monothetic classification. Forty-one varieties were classified into four groups (I, II, III and IV) with weighted variable group method (WVGM ) and weighted jai. group method(WPGM), whereas the results classification of 33 varieties among them by WVGM were coincident with the results by WPGM. As for the characteristics of each group, group I related to late maturity, tall height and high yield, group II related to intermediate maturity, tall height and low yield, group 19 related to early maturity, intermediate height and low yield, and group W related to early maturity, short height and intermediate yield.

  • PDF

Structrual Dynamic Analysis of a Diving Springboard to Reach Settled Height - Using Co-rotational Formulation (다이버가 일정한 높이로 도약 시 CR기법을 이용한 스프링보드의 구조 동역학적 해석)

  • Lee, Ji-Woo;Lee, Sang-Yeob;Lee, Sang-Hyeon
    • Proceeding of EDISON Challenge
    • /
    • 2016.03a
    • /
    • pp.217-221
    • /
    • 2016
  • In this paper, a springboard for diving is analysed to find out how much force a diver should apply to reach specific height when the diver jumps. The springboard is presumed to Co-rotational plane cantilever beam(CR-beam), so EDISON program related to Co-rotational framework is used. The force of the person is supposed to sine function and the demanded height is fixed. Same velocity makes same height regardless of diver's weight. So, the velocity of springboard when the feet of a diver are separated from the springboard is a main factor of the analysis. The result shows that there is no association between deformation and weight and also between velocity and weight. That is, the required force to reach a optimal height is fixed whatever the diver's weight is.

  • PDF

Validation of self-reported height and weight in fifth-grade Korean children

  • Lee, Bora;Chung, Sang-Jin;Lee, Soo-Kyung;Yoon, Jihyun
    • Nutrition Research and Practice
    • /
    • v.7 no.4
    • /
    • pp.326-329
    • /
    • 2013
  • Height and weight are important indicators to calculate Body Mass Index (BMI); measuring height and weight directly is the most exact method to get this information. However, it is ineffective in terms of cost and time on large population samples. The aim of our study was to investigate the validity of self-reported height and weight data compared to our measured data in Korean children to predict obese status. Four hundred twenty-two fifth-grade (mean age $10.5{\pm}0.5$ years) children who had self-reported and measured height and weight data were final subjects for this study. Overweight/obese was defined as a BMI of or above the 85th percentile of the gender-specific BMI for age in the 2007 Korean National Growth Charts or a BMI of 25 or higher (underweight : < 5th, normal : ${\geq}5th$ to < 85th, overweight : ${\geq}85th$ to < 95th). The differences between self-reported and measured data were tested using paired t-test. Differences based on overweight/obese status were tested using analysis of variance (ANOVA) and linear trends. Pearson's correlation and Cohen's kappa were tested to examine agreements between the self-reported and measured data. Although measured and self-reported height, weight and BMI were significantly different and children tended to overreport their height and underreport their weight, the correlation between the two methods of height, weight and BMI were high (r = 0.956, 0.969, 0.932, respectively; all P < 0.001), and both genders reported their overweight/non-overweight status accurately (Cohen's kappa = 0.792, P < 0.001). Although there were differences between the self-reported and our measured methods, the self-reported weight and height was valid enough to classify overweight/obesity status correctly, especially in non-overweight/obese children. Due to bigger underestimation of weight and overestimation of height in obese children, however, we need to be aware that the self-reported anthropometric data were less accurate in overweight/obese children than in non-overweight/obese children.

Implementation of Automatic 4 Points OPU Skew Adjustment Device with Height Compensation (높이 보정이 가능한 자동4점 Optical PICK-UP Skew 조정장치 구현)

  • Oh, Dong-Kyu
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.1095-1096
    • /
    • 2008
  • By adding height compensation to the usual 3 points skew adjustment device, an improved functional skew adjustment device is implemented in this paper. The proposed skew adjustment device is for traverse which will be adapted to BD and HD player system requiring more accuracy. and It can adjust not only R/T skew but also height. The system is composed of personal computer, control box, kinematic mechanism device and bar-code reader device. Application programs are implemented by visual basic.

  • PDF

Muscle Activation Change of Rectus Abdominal Muscle and Erector Spinae Muscle depending on Shoe Heel-height on Gait (구두 굽 높이에 따른 보행시 복직근과 기립근의 근활성도 변화)

  • Kim, Seong-Gil;Im, Dong-Ho;Kong, Eung-Kyung
    • Journal of Korean Physical Therapy Science
    • /
    • v.19 no.2
    • /
    • pp.1-7
    • /
    • 2012
  • Purpose : The purpose of this study was to investigate the effect of different heel height on the electromyographic (EMG) activity in Rectus abdominis (RA) and Erector spinae (ES) during gait activity. Methods : A repeated measures design was used. 33 healthy females carried out a standardized gait activity under 3 conditions; with heel wedges of 1, 7, and 12cm in height. EMG activity was recorded from RA and ES during the activity. Data was analysed using the repeated one-way ANOVA. Results : First, as the shoe-heel height was getting higher, change of muscle activation indicated the statistically significant difference in rectus abdominis(p<0.05). Second, as the shoe-heel height was getting higher, change of muscle activation indicated the statistically significant difference in erector spinae(p<0.05). Conclusion : We found that as heel height increased, there was an increase in EMG activity in both RA and ES. This indicated that no RA : ES imbalance was elicited. This study provides information that will inform future research on how heel height affects muscle activity around the trunk.

  • PDF

Center point prediction using Gaussian elliptic and size component regression using small solution space for object detection

  • Yuantian Xia;Shuhan Lu;Longhe Wang;Lin Li
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.8
    • /
    • pp.1976-1995
    • /
    • 2023
  • The anchor-free object detector CenterNet regards the object as a center point and predicts it based on the Gaussian circle region. For each object's center point, CenterNet directly regresses the width and height of the objects and finally gets the boundary range of the objects. However, the critical range of the object's center point can not be accurately limited by using the Gaussian circle region to constrain the prediction region, resulting in many low-quality centers' predicted values. In addition, because of the large difference between the width and height of different objects, directly regressing the width and height will make the model difficult to converge and lose the intrinsic relationship between them, thereby reducing the stability and consistency of accuracy. For these problems, we proposed a center point prediction method based on the Gaussian elliptic region and a size component regression method based on the small solution space. First, we constructed a Gaussian ellipse region that can accurately predict the object's center point. Second, we recode the width and height of the objects, which significantly reduces the regression solution space and improves the convergence speed of the model. Finally, we jointly decode the predicted components, enhancing the internal relationship between the size components and improving the accuracy consistency. Experiments show that when using CenterNet as the improved baseline and Hourglass-104 as the backbone, on the MS COCO dataset, our improved model achieved 44.7%, which is 2.6% higher than the baseline.

Accuracy Evaluation of the Height Determined by Network-RTK VRS Positioning (네트워크 RTK VRS 측량에 의한 표고정확도 평가)

  • Lee, Suk Bae
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.21 no.4
    • /
    • pp.55-63
    • /
    • 2013
  • Network-RTK GPS positioning technique based on national CORS(Continuous Operating Reference Station) and wireless internet access as like VRS and FKP was developed to overcome the limitations of traditional RTK technique. In Korea, NGII(National Geographic Information Institute) provides network-RTK service based on 51 CORS and mobile internet network. The purpose of this study is the accuracy evaluation of the height determined by GPS VRS technique based on network-RTK, So, in this study GPS VRS positioning was accomplished through 1st level BM line located at Sancheong~Jinju and $2^{nd}$ level BM line located at Geochang~Sancheong and the average error of the each BM line was calculated as 2.15cm and 1.80cm respectively. This result shows that GPS VRS height positioning can be used in $3^{rd}$ and 4th public BM leveling and also work regulation is needed to apply the GPS VRS height positioning.